Catch receptacle for evacuative suction apparatus



Feb. 28, 1967 .1. K. MITCHELL.

CATCH REGEPTACLE FOR EVACUATIVE SUCTION APPARATUS Filed Oct. 2, 1964 F/G Z.

INVENTOR. JOSEPH K M|TCHELL TTORNEYS United States Patent poration of Utah Filed Oct. 2, 1964, Ser. No. 401,138 3 Claims. (Cl. 3233) This invention relates to receptacles adapted to be interposed in suction lines to catch liquids and solids entrained in air being sucked through such lines.

In US. Patents Numbers 2,784,717 and 3,017,886, granted to Elbert 0. Thompson, there are disclosed different forms of evacuative suction apparatus which include catch receptacles for removing liquids and solids from high volume streams of air in which they are entrained pursuant to a unique method of dentistry wherein wash water is applied to and evacuated, along with saliva and debris, from areas of the mouth being worked on, see U.S. Patent Number 3,012,323, also granted to Elbert 0. Thompson.

These catch receptacles make use of electrodes and electrical devices in circuit therewith for controlling operation of the motor-fan units employed to produce suction. Other apparatus of the type concerned utilize catch receptacles employing floats and electrical control devices, see Winter US. Patent No. Re. 24,755 and Jones US. Patent No. 3,078,579.

The present invention constitutes an improvement on the catch receptacles of the latter type and has for its principal object to provide a receptacle in which suction applied thereto is positively cut-off when a predetermined level of liquid has been accumulated, the liquid then being automatically discharged, without the necessity for any electrical sensing or control means.

Another important object is to provide a catch receptacle that will operate to discharge liquid accumulated therein even though the source of suction continues to apply suction necessary for continued operation of additional catch receptacles or of other apparatus connected thereto.

An outstanding feature of the invention is the provision of a housing containing a liquid level responsive shut-off valve positioned in the evacuative air path and arranged to cut-off flow of the air through the housing when the level of liquid trapped therein reaches a predetermined height.

The shut-otf valve is advantageously positioned in a hollow, inverted, truncated cone, the flared upper end of which provides a low velocity zone in the evacuative air path and also forms a baffle between an inlet nozzle and a suction outlet. The low velocity zone and the baflle =both contribute to settlement of liquid and solids carried by the air stream into the housing, and insure that no liquid or solid materials are carried to the suction fan.

There is shown in the accompanying drawing a specific embodiment of the invention representing what is presently regarded as the best mode of carrying out the generic concepts in actual practice. From the detailed description of this presently preferred form of the invention, other more specific objects and features will become apparent.

In the drawing:

FIG. 1 is a side elevation of the catch receptacle of the invention;

FIG. 2, a top plan view;

FIG. 3 a top plan view with the lid removed;

FIG. 4, a vertical section taken on the line 44 of FIG. 2; and

FIG. 5, a vertical section taken on line 5-5 of FIG. 3.

Referring now to the drawing:

In the illustrated preferred embodiment the catch receptacle 10 includes an open topped housing 11 and a lid 12. Toggle type latches 13 are fixed to the side of housing 11; in their locked position they engage recesses 14 formed in a lid 12 to sealingly hold the lower edge 15 of lid 12 against the rim 16 of the housing.

An inlet nozzle 17 is carried by lid 12, being journaled therein for swiveling movement. This nozzle includes a hose-receiving end 18 and an end 19 that depends from lid 12 downwardly into housing 11 when the lid is positioned on the housing. A groove 20 surrounds end 19, and a drawstring 21 of a filter bag 22 of suitable porous material is tightly but releasably tied in the groove. Thus, substantially all precious metals and most other solid materials carried into the housing through the nozzle are caught in the bag. Liquid and air pass freely through the bag, the liquid collecting in the bottom of the housing in a manner to be described.

Air, liquid, and debris are sucked in through the free end of a flexible hose (not shown) connected to end 18 of nozzle 17, and are carried through nozzle 17 and into filter bag 22. Air, liquid, and any debris not retained by the filter bag pass into housing 11. From there, the air passes through a batfle 23 of inverted and truncated cone shape, through riser 23a supporting the bafile, and through an outlet hose 24 connected at the bottom of riser 23a to a source of suction, also not shown.

Baflle 23 is eccentrically mounted within housing 11 such that, when lid 12 is positioned on the housing, the end 19 of nozzle 17 is adjacent the baflle and extends slightly below its top rim 23b. The off-center mounting of baffle 23 allows free travel of a float 25 within housing 11, as will be explained.

As the air, including its entrained liquid and any solids not retained by the bag, passes through filter bag 22 into housing 11, the increased size of the opening through which it passes, i.e. the interior of the housing, creates a low velocity zone in which the speed of travel of the air is decreased sufficiently to allow the moisture and any solid particles that may have passed through the filter bag to drop out from the air stream and settle at the bottom of the housing.

The positioning of end 19 of nozzle 17 below rim 23b of baffle 23 also assists in settling the liquid and retained solids out of the air, since they impinge on the outwardly flared wall of the baflle, rather than being carried with the air up, over, and out through the bafile and outlet hose 24 into the source of suction, normally a motor-fan unit which can be severely damaged by moisture.

The inverted truncated cone shape of the baflle provides a gradual reduction in the size of the flow path for the cleansed air from the upper flared end of such baflle down to riser 23a and prevents a velocity increase at such flared end that would tend to draw into the baflle, with the air, as yet unsettled drops of liquid and solid particles.

As the drop-out liquid in the housing accumulates and its level rises, weighted float 25 rides thereon and pivots arm 26 about pivot pin 27 as it rises, thereby lowering valve 28 and ultimately seating it over the air out-flow opening leading into riser 23a and from there into hose 24. Arm 26 is pivotally connected to the float by a linkage arm 29 and to the valve by a linkage arm 30.

A slot 230 is provided in the side wall of baffle 23 to allow arm 26 to freely pivot, and pivot arm 26 is supported by post 23d extending upwardly from the bottom of the baflle.

The suction applied through outlet hose 24 assists in closing valve 28 and holds the valve in closed position until it is positively released. In this connection it is noted that the weight of float is insufficient to alone overcome the suction acting directly on the valve face to hold the valve closed.

When outlet hose 24 is closed, the housing is cut off Pivoted valve 31 normally closes a drain hose 32 con- 1 nected to a nipple 33 at the bottom of housing 11, but opens to allow free gravity flow of liquid through the drain hose to a waste system (not shown) when the 1 vacuum in the housing is broken. The waste system can be specially designed, or existing systems can be employed. It is only necessary that the system allow gravity flow from the housing to waste.

or other resilient material.

Pivoted valve 31 is desirably constructed of rubber The resiliency of the valve normally holds it seated upwardly against nipple 33.

The Vacuum created in the housing assists in holding valve 31 closed, even when liquid has accumulated thereon. When the vacuum is cut-off, as by valve 28 closing in response to suflicient raising of the liquid level, or due to a shut-down of the entire vacuum system, the weight of liquid acting on check valve 31 forces it to swing open so that the liquid can drain out.

Even though the liquid has drained, float 25 will be held in its raised position by suction applied through conduit 24 to the face of valve 28. Thus, reset means are required to move the valve off its seat so that the float will drop and the unit will be ready for another cycle of operation. The reset means consists of a member 34 having an enlarged portion 35 inside lid 12 of housing 11 and an enlarged head portion 36 outside.

Spring 37 surrounds a shank 38 that extends between enlarged portions 35 and 36 and is positioned between the lid and head portion 36 such that enlarged portion 35 is normally held against the lid. When the lid is properly positioned and the liquid has drained from housing 11, member 34 is manually depressed to force enlarged portion 35 against arm 26, there-by pivoting the arm and raising the valve. Once the valve has been moved away from the direct application of suction through conduit 24, the weight of the float is sufiicient to continue pivoting of arm 26 and to hold the valve open until the float is again raised by accumulated liquid.

In order to facilitate mounting of the catch receptacle, a mounting bracket 40 is bolted to the housing with bolts 41. Holes 42 are provided through the bracket to receive additional bolts or screws for fastening the bracket in position.

I have thus provided a catch receptacle that will trap liquid and solid particles entrained in an evacuative air stream before they are carried with such stream to a suction-producing apparatus, such as a motor-fan unit; a catch receptacle that will automatically and periodiically dump the accumulated liquid; and one that is easily reset for another period of operation. Since the source of suction does not have to be shut off during the automatic draining operation, other similar catch receptacles in an overall system or different equipment utilizing the same source of suction can continue uninterrupted operation.

Whereas there is here illustrated and specifically described a certain preferred construction of apparatus which is presently regarded as the best mode of carrying out the invention, it should be understood that various changes may be made and other construction adopted without departing from the inventive subject matter particularly pointed out and claimed herebelow.

I claim:

1. A catch receptacle for use in evacuative suction apparatus comprising a housing;

an air inlet to said housing;

a drain from said housing;

an evacuative air flow conduit extending upwardly into the housing;

a baflie surrounding the terminal end of said evacuative air flow conduit in the housing and being flared upwardly and outwardly therefrom;

a valve positioned within said baflie;

a float in said housing and outside said baffle;

means interconnecting said float, and said valve, whereby a predetermined accumulation of liquid in said housing raises said float to move the valve to a position closing the terminal end of said evacuative air flow conduit in the housing;

means for moving said valve from its position closing the conduit to an open position in opposition to suction in the conduit acting on the said valve, when liquid in the housing is below a predetermined level; and

means closing said drain from the housing when a vacuum exists in said housing, but movable to an open position in the absence of such a vacuum.

2. A catch receptacle according to claim 1, further including a removable lid for the housing; and wherein the means for moving the valve from its position closing the evacuative air flow conduit comprises a plunger extending through the lid and adapted, when depressed, to contact the means interconnecting the valve and the float to thereby lower the float and raise the valve from the conduit; and

means normally biasing the plunger to a raised position.

3. A catch receptacle according to claim 2, wherein the means closing the drain from the housing when a vacuum exists in the housing comprises a pivoted valve of resilient material that is self-biasing to drain closing position but that is movable to open position under the weight of liquid in the housing.

References Cited by the Examiner UNITED STATES PATENTS 1,202,971 10/1916 Daiber 128-277 2,274,893 3/1942 Freedman 3233 2,821,021 1/1958 Winter 32.33 3,051,175 8/1962 Nugent 128276 3,078,579 2/1963 Jones et al. 32-33 3,138,973 6/1964 Bisho 3233 RICHARD A. GAUDET, Primary Examiner.

J. W. HINEY, Assistant Examiner. 

1. A CATCH RECEPTACLE FOR USE IN EVACUATIVE SUCTION APPARATUS COMPRISING A HOUSING; AN AIR INLET TO SAID HOUSING; A DRAIN FROM SAID HOUSING; AN EVACUATIVE AIR FLOW CONDUIT EXTENDING UPWARDLY INTO THE HOUSING; A BAFFLE SURROUNDING THE TERMINAL END OF SAID EVACUATIVE AIR FLOW CONDUIT IN THE HOUSING AND BEING FLARED UPWARDLY AND OUTWARDLY THEREFROM; A VALVE POSITIONED WITHIN SAID BAFFLE; A FLOAT IN SAID HOUSING AND OUTSIDE SAID BAFFLE; MEANS INTERCONNECTING SAID FLOAT, AND SAID VALVE, WHEREBY A PREDETERMINED ACCUMULATION OF LIQUID IN SAID HOUSING RAISES SAID FLOAT TO MOVE THE VALVE TO A POSITION CLOSING THE TERMINAL END OF SAID EVACUATIVE AIR FLOW CONDUIT IN THE HOUSING; MEANS FOR MOVING SAID VALVE FROM ITS POSITION CLOSING THE CONDUIT TO AN OPEN POSITION IN OPPOSITION TO SUCTION IN THE CONDUIT ACTING ON THE SAID VALVE, WHEN LIQUID IN THE HOUSING IS BELOW A PREDETERMINED LEVEL; AND MEANS CLOSING SAID DRAIN FROM THE HOUSING WHEN A VACUUM EXISTS IN SAID HOUSING, BUT MOVABLE TO AN OPEN POSITION IN THE ABSENCE OF SUCH A VACUUM. 